[PATCH V3 5/5] PCI: tegra: Add support for PCIe endpoint mode in Tegra194

From: Vidya Sagar
Date: Mon Jan 13 2020 - 13:15:00 EST


Add support for the endpoint mode of Synopsys DesignWare core based
dual mode PCIe controllers present in Tegra194 SoC.

Signed-off-by: Vidya Sagar <vidyas@xxxxxxxxxx>
---
V3:
* Addressed Thierry's review comments

V2:
* Addressed Bjorn's review comments
* Made changes as part of addressing review comments for other patches

drivers/pci/controller/dwc/Kconfig | 30 +-
drivers/pci/controller/dwc/pcie-tegra194.c | 770 ++++++++++++++++++++-
2 files changed, 782 insertions(+), 18 deletions(-)

diff --git a/drivers/pci/controller/dwc/Kconfig b/drivers/pci/controller/dwc/Kconfig
index 0830dfcfa43a..169cde58dd92 100644
--- a/drivers/pci/controller/dwc/Kconfig
+++ b/drivers/pci/controller/dwc/Kconfig
@@ -248,14 +248,38 @@ config PCI_MESON
implement the driver.

config PCIE_TEGRA194
- tristate "NVIDIA Tegra194 (and later) PCIe controller"
+ tristate
+
+config PCIE_TEGRA194_HOST
+ tristate "NVIDIA Tegra194 (and later) PCIe controller - Host Mode"
depends on ARCH_TEGRA_194_SOC || COMPILE_TEST
depends on PCI_MSI_IRQ_DOMAIN
select PCIE_DW_HOST
select PHY_TEGRA194_P2U
+ select PCIE_TEGRA194
+ default y
+ help
+ Enables support for the PCIe controller in the NVIDIA Tegra194 SoC to
+ work in host mode. There are two instances of PCIe controllers in
+ Tegra194. This controller can work either as EP or RC. In order to
+ enable host-specific features PCIE_TEGRA194_HOST must be selected and
+ in order to enable device-specific features PCIE_TEGRA194_EP must be
+ selected. This uses the DesignWare core.
+
+config PCIE_TEGRA194_EP
+ tristate "NVIDIA Tegra194 (and later) PCIe controller - Endpoint Mode"
+ depends on ARCH_TEGRA_194_SOC || COMPILE_TEST
+ depends on PCI_ENDPOINT
+ select PCIE_DW_EP
+ select PHY_TEGRA194_P2U
+ select PCIE_TEGRA194
help
- Say Y here if you want support for DesignWare core based PCIe host
- controller found in NVIDIA Tegra194 SoC.
+ Enables support for the PCIe controller in the NVIDIA Tegra194 SoC to
+ work in host mode. There are two instances of PCIe controllers in
+ Tegra194. This controller can work either as EP or RC. In order to
+ enable host-specific features PCIE_TEGRA194_HOST must be selected and
+ in order to enable device-specific features PCIE_TEGRA194_EP must be
+ selected. This uses the DesignWare core.

config PCIE_UNIPHIER
bool "Socionext UniPhier PCIe controllers"
diff --git a/drivers/pci/controller/dwc/pcie-tegra194.c b/drivers/pci/controller/dwc/pcie-tegra194.c
index cbe95f0ea0ca..8152e7be2771 100644
--- a/drivers/pci/controller/dwc/pcie-tegra194.c
+++ b/drivers/pci/controller/dwc/pcie-tegra194.c
@@ -14,6 +14,8 @@
#include <linux/interrupt.h>
#include <linux/iopoll.h>
#include <linux/kernel.h>
+#include <linux/kfifo.h>
+#include <linux/kthread.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
@@ -53,6 +55,7 @@
#define APPL_INTR_EN_L0_0_LINK_STATE_INT_EN BIT(0)
#define APPL_INTR_EN_L0_0_MSI_RCV_INT_EN BIT(4)
#define APPL_INTR_EN_L0_0_INT_INT_EN BIT(8)
+#define APPL_INTR_EN_L0_0_PCI_CMD_EN_INT_EN BIT(15)
#define APPL_INTR_EN_L0_0_CDM_REG_CHK_INT_EN BIT(19)
#define APPL_INTR_EN_L0_0_SYS_INTR_EN BIT(30)
#define APPL_INTR_EN_L0_0_SYS_MSI_INTR_EN BIT(31)
@@ -60,19 +63,26 @@
#define APPL_INTR_STATUS_L0 0xC
#define APPL_INTR_STATUS_L0_LINK_STATE_INT BIT(0)
#define APPL_INTR_STATUS_L0_INT_INT BIT(8)
+#define APPL_INTR_STATUS_L0_PCI_CMD_EN_INT BIT(15)
+#define APPL_INTR_STATUS_L0_PEX_RST_INT BIT(16)
#define APPL_INTR_STATUS_L0_CDM_REG_CHK_INT BIT(18)

#define APPL_INTR_EN_L1_0_0 0x1C
#define APPL_INTR_EN_L1_0_0_LINK_REQ_RST_NOT_INT_EN BIT(1)
+#define APPL_INTR_EN_L1_0_0_RDLH_LINK_UP_INT_EN BIT(3)
+#define APPL_INTR_EN_L1_0_0_HOT_RESET_DONE_INT_EN BIT(30)

#define APPL_INTR_STATUS_L1_0_0 0x20
#define APPL_INTR_STATUS_L1_0_0_LINK_REQ_RST_NOT_CHGED BIT(1)
+#define APPL_INTR_STATUS_L1_0_0_RDLH_LINK_UP_CHGED BIT(3)
+#define APPL_INTR_STATUS_L1_0_0_HOT_RESET_DONE BIT(30)

#define APPL_INTR_STATUS_L1_1 0x2C
#define APPL_INTR_STATUS_L1_2 0x30
#define APPL_INTR_STATUS_L1_3 0x34
#define APPL_INTR_STATUS_L1_6 0x3C
#define APPL_INTR_STATUS_L1_7 0x40
+#define APPL_INTR_STATUS_L1_15_CFG_BME_CHGED BIT(1)

#define APPL_INTR_EN_L1_8_0 0x44
#define APPL_INTR_EN_L1_8_BW_MGT_INT_EN BIT(2)
@@ -103,8 +113,12 @@
#define APPL_INTR_STATUS_L1_18_CDM_REG_CHK_CMP_ERR BIT(1)
#define APPL_INTR_STATUS_L1_18_CDM_REG_CHK_LOGIC_ERR BIT(0)

+#define APPL_MSI_CTRL_1 0xAC
+
#define APPL_MSI_CTRL_2 0xB0

+#define APPL_LEGACY_INTX 0xB8
+
#define APPL_LTR_MSG_1 0xC4
#define LTR_MSG_REQ BIT(15)
#define LTR_MST_NO_SNOOP_SHIFT 16
@@ -205,6 +219,13 @@
#define AMBA_ERROR_RESPONSE_CRS_OKAY_FFFFFFFF 1
#define AMBA_ERROR_RESPONSE_CRS_OKAY_FFFF0001 2

+#define MSIX_ADDR_MATCH_LOW_OFF 0x940
+#define MSIX_ADDR_MATCH_LOW_OFF_EN BIT(0)
+#define MSIX_ADDR_MATCH_LOW_OFF_MASK GENMASK(31, 2)
+
+#define MSIX_ADDR_MATCH_HIGH_OFF 0x944
+#define MSIX_ADDR_MATCH_HIGH_OFF_MASK GENMASK(31, 0)
+
#define PORT_LOGIC_MSIX_DOORBELL 0x948

#define CAP_SPCIE_CAP_OFF 0x154
@@ -223,6 +244,25 @@
#define GEN3_CORE_CLK_FREQ 250000000
#define GEN4_CORE_CLK_FREQ 500000000

+#define LTR_MSG_TIMEOUT (100 * 1000)
+
+#define PERST_DEBOUNCE_TIME (5 * 1000)
+
+#define EVENT_QUEUE_LEN (256)
+
+#define EP_STATE_DISABLED 0
+#define EP_STATE_ENABLED 1
+
+enum ep_event {
+ EP_EVENT_NONE = 0,
+ EP_PEX_RST_DEASSERT,
+ EP_PEX_RST_ASSERT,
+ EP_HOT_RST_DONE,
+ EP_BME_CHANGE,
+ EP_EVENT_EXIT,
+ EP_EVENT_INVALID,
+};
+
static const unsigned int pcie_gen_freq[] = {
GEN1_CORE_CLK_FREQ,
GEN2_CORE_CLK_FREQ,
@@ -260,6 +300,8 @@ struct tegra_pcie_dw {
struct dw_pcie pci;
struct tegra_bpmp *bpmp;

+ enum dw_pcie_device_mode mode;
+
bool supports_clkreq;
bool enable_cdm_check;
bool link_state;
@@ -283,6 +325,19 @@ struct tegra_pcie_dw {
struct phy **phys;

struct dentry *debugfs;
+
+ /* Endpoint mode specific */
+ struct task_struct *pcie_ep_task;
+ wait_queue_head_t wq;
+ struct gpio_desc *pex_rst_gpiod;
+ struct gpio_desc *pex_refclk_sel_gpiod;
+ unsigned int pex_rst_irq;
+ int ep_state;
+ DECLARE_KFIFO(event_fifo, u32, EVENT_QUEUE_LEN);
+};
+
+struct tegra_pcie_dw_of_data {
+ enum dw_pcie_device_mode mode;
};

static inline struct tegra_pcie_dw *to_tegra_pcie(struct dw_pcie *pci)
@@ -339,8 +394,9 @@ static void apply_bad_link_workaround(struct pcie_port *pp)
}
}

-static irqreturn_t tegra_pcie_rp_irq_handler(struct tegra_pcie_dw *pcie)
+static irqreturn_t tegra_pcie_rp_irq_handler(int irq, void *arg)
{
+ struct tegra_pcie_dw *pcie = arg;
struct dw_pcie *pci = &pcie->pci;
struct pcie_port *pp = &pci->pp;
u32 val, tmp;
@@ -411,11 +467,60 @@ static irqreturn_t tegra_pcie_rp_irq_handler(struct tegra_pcie_dw *pcie)
return IRQ_HANDLED;
}

-static irqreturn_t tegra_pcie_irq_handler(int irq, void *arg)
+static irqreturn_t tegra_pcie_ep_irq_handler(int irq, void *arg)
{
struct tegra_pcie_dw *pcie = arg;
+ struct dw_pcie_ep *ep = &pcie->pci.ep;
+ int spurious = 1;
+ u32 val, tmp;

- return tegra_pcie_rp_irq_handler(pcie);
+ val = appl_readl(pcie, APPL_INTR_STATUS_L0);
+ if (val & APPL_INTR_STATUS_L0_LINK_STATE_INT) {
+ val = appl_readl(pcie, APPL_INTR_STATUS_L1_0_0);
+ appl_writel(pcie, val, APPL_INTR_STATUS_L1_0_0);
+
+ if (val & APPL_INTR_STATUS_L1_0_0_HOT_RESET_DONE) {
+ /* clear any stale PEX_RST interrupt */
+ if (!kfifo_put(&pcie->event_fifo, EP_HOT_RST_DONE)) {
+ dev_err(pcie->dev, "EVENT FIFO is full\n");
+ return IRQ_HANDLED;
+ }
+ wake_up(&pcie->wq);
+ }
+
+ if (val & APPL_INTR_STATUS_L1_0_0_RDLH_LINK_UP_CHGED) {
+ tmp = appl_readl(pcie, APPL_LINK_STATUS);
+ if (tmp & APPL_LINK_STATUS_RDLH_LINK_UP) {
+ dev_dbg(pcie->dev, "Link is up with Host\n");
+ dw_pcie_ep_linkup(ep);
+ }
+ }
+
+ spurious = 0;
+ }
+
+ if (val & APPL_INTR_STATUS_L0_PCI_CMD_EN_INT) {
+ val = appl_readl(pcie, APPL_INTR_STATUS_L1_15);
+ appl_writel(pcie, val, APPL_INTR_STATUS_L1_15);
+
+ if (val & APPL_INTR_STATUS_L1_15_CFG_BME_CHGED) {
+ if (!kfifo_put(&pcie->event_fifo, EP_BME_CHANGE)) {
+ dev_err(pcie->dev, "EVENT FIFO is full\n");
+ return IRQ_HANDLED;
+ }
+ wake_up(&pcie->wq);
+ }
+
+ spurious = 0;
+ }
+
+ if (spurious) {
+ dev_warn(pcie->dev, "Random interrupt (STATUS = 0x%08X)\n",
+ val);
+ appl_writel(pcie, val, APPL_INTR_STATUS_L0);
+ }
+
+ return IRQ_HANDLED;
}

static int tegra_pcie_dw_rd_own_conf(struct pcie_port *pp, int where, int size,
@@ -884,8 +989,26 @@ static void tegra_pcie_set_msi_vec_num(struct pcie_port *pp)
pp->num_vectors = MAX_MSI_IRQS;
}

+static int tegra_pcie_dw_start_link(struct dw_pcie *pci)
+{
+ struct tegra_pcie_dw *pcie = to_tegra_pcie(pci);
+
+ enable_irq(pcie->pex_rst_irq);
+
+ return 0;
+}
+
+static void tegra_pcie_dw_stop_link(struct dw_pcie *pci)
+{
+ struct tegra_pcie_dw *pcie = to_tegra_pcie(pci);
+
+ disable_irq(pcie->pex_rst_irq);
+}
+
static const struct dw_pcie_ops tegra_dw_pcie_ops = {
.link_up = tegra_pcie_dw_link_up,
+ .start_link = tegra_pcie_dw_start_link,
+ .stop_link = tegra_pcie_dw_stop_link,
};

static struct dw_pcie_host_ops tegra_pcie_dw_host_ops = {
@@ -986,6 +1109,26 @@ static int tegra_pcie_dw_parse_dt(struct tegra_pcie_dw *pcie)
pcie->enable_cdm_check =
of_property_read_bool(np, "snps,enable-cdm-check");

+ if (pcie->mode == DW_PCIE_RC_TYPE)
+ return 0;
+
+ /* Endpoint mode specific DT entries */
+ pcie->pex_rst_gpiod = devm_gpiod_get(pcie->dev, "reset", GPIOD_IN);
+ if (IS_ERR(pcie->pex_rst_gpiod)) {
+ dev_err(pcie->dev, "Failed to get PERST GPIO: %ld\n",
+ PTR_ERR(pcie->pex_rst_gpiod));
+ return PTR_ERR(pcie->pex_rst_gpiod);
+ }
+
+ pcie->pex_refclk_sel_gpiod = devm_gpiod_get(pcie->dev,
+ "nvidia,refclk-select",
+ GPIOD_OUT_HIGH);
+ if (IS_ERR(pcie->pex_refclk_sel_gpiod)) {
+ dev_info(pcie->dev, "Failed to get REFCLK select GPIOs: %ld\n",
+ PTR_ERR(pcie->pex_refclk_sel_gpiod));
+ pcie->pex_refclk_sel_gpiod = NULL;
+ }
+
return 0;
}

@@ -1017,6 +1160,34 @@ static int tegra_pcie_bpmp_set_ctrl_state(struct tegra_pcie_dw *pcie,
return tegra_bpmp_transfer(pcie->bpmp, &msg);
}

+static int tegra_pcie_bpmp_set_pll_state(struct tegra_pcie_dw *pcie,
+ bool enable)
+{
+ struct mrq_uphy_response resp;
+ struct tegra_bpmp_message msg;
+ struct mrq_uphy_request req;
+
+ memset(&req, 0, sizeof(req));
+ memset(&resp, 0, sizeof(resp));
+
+ if (enable) {
+ req.cmd = CMD_UPHY_PCIE_EP_CONTROLLER_PLL_INIT;
+ req.ep_ctrlr_pll_init.ep_controller = pcie->cid;
+ } else {
+ req.cmd = CMD_UPHY_PCIE_EP_CONTROLLER_PLL_OFF;
+ req.ep_ctrlr_pll_off.ep_controller = pcie->cid;
+ }
+
+ memset(&msg, 0, sizeof(msg));
+ msg.mrq = MRQ_UPHY;
+ msg.tx.data = &req;
+ msg.tx.size = sizeof(req);
+ msg.rx.data = &resp;
+ msg.rx.size = sizeof(resp);
+
+ return tegra_bpmp_transfer(pcie->bpmp, &msg);
+}
+
static void tegra_pcie_downstream_dev_to_D0(struct tegra_pcie_dw *pcie)
{
struct pcie_port *pp = &pcie->pci.pp;
@@ -1427,8 +1598,534 @@ static int tegra_pcie_config_rp(struct tegra_pcie_dw *pcie)
return ret;
}

+static void pex_ep_event_pex_rst_assert(struct tegra_pcie_dw *pcie)
+{
+ u32 val;
+ int ret;
+
+ if (pcie->ep_state == EP_STATE_DISABLED)
+ return;
+
+ /* Disable LTSSM */
+ val = appl_readl(pcie, APPL_CTRL);
+ val &= ~APPL_CTRL_LTSSM_EN;
+ appl_writel(pcie, val, APPL_CTRL);
+
+ ret = readl_poll_timeout(pcie->appl_base + APPL_DEBUG, val,
+ ((val & APPL_DEBUG_LTSSM_STATE_MASK) >>
+ APPL_DEBUG_LTSSM_STATE_SHIFT) ==
+ LTSSM_STATE_PRE_DETECT,
+ 1, LTSSM_TIMEOUT);
+ if (ret)
+ dev_err(pcie->dev, "Failed to go Detect state: %d\n", ret);
+
+ reset_control_assert(pcie->core_rst);
+
+ tegra_pcie_disable_phy(pcie);
+
+ reset_control_assert(pcie->core_apb_rst);
+
+ clk_disable_unprepare(pcie->core_clk);
+
+ pm_runtime_put_sync(pcie->dev);
+
+ ret = tegra_pcie_bpmp_set_pll_state(pcie, false);
+ if (ret)
+ dev_err(pcie->dev, "Failed to turn off UPHY: %d\n", ret);
+
+ pcie->ep_state = EP_STATE_DISABLED;
+ dev_dbg(pcie->dev, "Uninitialization of endpoint is completed\n");
+}
+
+static void pex_ep_event_pex_rst_deassert(struct tegra_pcie_dw *pcie)
+{
+ struct dw_pcie *pci = &pcie->pci;
+ struct dw_pcie_ep *ep = &pci->ep;
+ struct device *dev = pcie->dev;
+ u32 val;
+ int ret;
+
+ if (pcie->ep_state == EP_STATE_ENABLED)
+ return;
+
+ ret = pm_runtime_get_sync(dev);
+ if (ret < 0) {
+ dev_err(dev, "Failed to get runtime sync for PCIe dev: %d\n",
+ ret);
+ return;
+ }
+
+ ret = tegra_pcie_bpmp_set_pll_state(pcie, true);
+ if (ret) {
+ dev_err(dev, "Failed to init UPHY for PCIe EP: %d\n", ret);
+ goto fail_pll_init;
+ }
+
+ ret = clk_prepare_enable(pcie->core_clk);
+ if (ret) {
+ dev_err(dev, "Failed to enable core clock: %d\n", ret);
+ goto fail_core_clk_enable;
+ }
+
+ ret = reset_control_deassert(pcie->core_apb_rst);
+ if (ret) {
+ dev_err(dev, "Failed to deassert core APB reset: %d\n", ret);
+ goto fail_core_apb_rst;
+ }
+
+ ret = tegra_pcie_enable_phy(pcie);
+ if (ret) {
+ dev_err(dev, "Failed to enable PHY: %d\n", ret);
+ goto fail_phy;
+ }
+
+ /* Clear any stale interrupt statuses */
+ appl_writel(pcie, 0xFFFFFFFF, APPL_INTR_STATUS_L0);
+ appl_writel(pcie, 0xFFFFFFFF, APPL_INTR_STATUS_L1_0_0);
+ appl_writel(pcie, 0xFFFFFFFF, APPL_INTR_STATUS_L1_1);
+ appl_writel(pcie, 0xFFFFFFFF, APPL_INTR_STATUS_L1_2);
+ appl_writel(pcie, 0xFFFFFFFF, APPL_INTR_STATUS_L1_3);
+ appl_writel(pcie, 0xFFFFFFFF, APPL_INTR_STATUS_L1_6);
+ appl_writel(pcie, 0xFFFFFFFF, APPL_INTR_STATUS_L1_7);
+ appl_writel(pcie, 0xFFFFFFFF, APPL_INTR_STATUS_L1_8_0);
+ appl_writel(pcie, 0xFFFFFFFF, APPL_INTR_STATUS_L1_9);
+ appl_writel(pcie, 0xFFFFFFFF, APPL_INTR_STATUS_L1_10);
+ appl_writel(pcie, 0xFFFFFFFF, APPL_INTR_STATUS_L1_11);
+ appl_writel(pcie, 0xFFFFFFFF, APPL_INTR_STATUS_L1_13);
+ appl_writel(pcie, 0xFFFFFFFF, APPL_INTR_STATUS_L1_14);
+ appl_writel(pcie, 0xFFFFFFFF, APPL_INTR_STATUS_L1_15);
+ appl_writel(pcie, 0xFFFFFFFF, APPL_INTR_STATUS_L1_17);
+
+ /* configure this core for EP mode operation */
+ val = appl_readl(pcie, APPL_DM_TYPE);
+ val &= ~APPL_DM_TYPE_MASK;
+ val |= APPL_DM_TYPE_EP;
+ appl_writel(pcie, val, APPL_DM_TYPE);
+
+ appl_writel(pcie, 0x0, APPL_CFG_SLCG_OVERRIDE);
+
+ val = appl_readl(pcie, APPL_CTRL);
+ val |= APPL_CTRL_SYS_PRE_DET_STATE;
+ val |= APPL_CTRL_HW_HOT_RST_EN;
+ appl_writel(pcie, val, APPL_CTRL);
+
+ val = appl_readl(pcie, APPL_CFG_MISC);
+ val |= APPL_CFG_MISC_SLV_EP_MODE;
+ val |= (APPL_CFG_MISC_ARCACHE_VAL << APPL_CFG_MISC_ARCACHE_SHIFT);
+ appl_writel(pcie, val, APPL_CFG_MISC);
+
+ val = appl_readl(pcie, APPL_PINMUX);
+ val |= APPL_PINMUX_CLK_OUTPUT_IN_OVERRIDE_EN;
+ val |= APPL_PINMUX_CLK_OUTPUT_IN_OVERRIDE;
+ appl_writel(pcie, val, APPL_PINMUX);
+
+ appl_writel(pcie, pcie->dbi_res->start & APPL_CFG_BASE_ADDR_MASK,
+ APPL_CFG_BASE_ADDR);
+
+ appl_writel(pcie, pcie->atu_dma_res->start &
+ APPL_CFG_IATU_DMA_BASE_ADDR_MASK,
+ APPL_CFG_IATU_DMA_BASE_ADDR);
+
+ val = appl_readl(pcie, APPL_INTR_EN_L0_0);
+ val |= APPL_INTR_EN_L0_0_SYS_INTR_EN;
+ val |= APPL_INTR_EN_L0_0_LINK_STATE_INT_EN;
+ val |= APPL_INTR_EN_L0_0_PCI_CMD_EN_INT_EN;
+ appl_writel(pcie, val, APPL_INTR_EN_L0_0);
+
+ val = appl_readl(pcie, APPL_INTR_EN_L1_0_0);
+ val |= APPL_INTR_EN_L1_0_0_HOT_RESET_DONE_INT_EN;
+ val |= APPL_INTR_EN_L1_0_0_RDLH_LINK_UP_INT_EN;
+ appl_writel(pcie, val, APPL_INTR_EN_L1_0_0);
+
+ reset_control_deassert(pcie->core_rst);
+
+ if (pcie->update_fc_fixup) {
+ val = dw_pcie_readl_dbi(pci, CFG_TIMER_CTRL_MAX_FUNC_NUM_OFF);
+ val |= 0x1 << CFG_TIMER_CTRL_ACK_NAK_SHIFT;
+ dw_pcie_writel_dbi(pci, CFG_TIMER_CTRL_MAX_FUNC_NUM_OFF, val);
+ }
+
+ config_gen3_gen4_eq_presets(pcie);
+
+ init_host_aspm(pcie);
+
+ /* Disable ASPM-L1SS advertisement if there is no CLKREQ routing */
+ if (!pcie->supports_clkreq) {
+ disable_aspm_l11(pcie);
+ disable_aspm_l12(pcie);
+ }
+
+ val = dw_pcie_readl_dbi(pci, GEN3_RELATED_OFF);
+ val &= ~GEN3_RELATED_OFF_GEN3_ZRXDC_NONCOMPL;
+ dw_pcie_writel_dbi(pci, GEN3_RELATED_OFF, val);
+
+ /* Configure N_FTS & FTS */
+ val = dw_pcie_readl_dbi(pci, PORT_LOGIC_ACK_F_ASPM_CTRL);
+ val &= ~(N_FTS_MASK << N_FTS_SHIFT);
+ val |= N_FTS_VAL << N_FTS_SHIFT;
+ dw_pcie_writel_dbi(pci, PORT_LOGIC_ACK_F_ASPM_CTRL, val);
+
+ val = dw_pcie_readl_dbi(pci, PORT_LOGIC_GEN2_CTRL);
+ val &= ~FTS_MASK;
+ val |= FTS_VAL;
+ dw_pcie_writel_dbi(pci, PORT_LOGIC_GEN2_CTRL, val);
+
+ /* Configure Max Speed from DT */
+ if (pcie->max_speed && pcie->max_speed != -EINVAL) {
+ val = dw_pcie_readl_dbi(pci, pcie->pcie_cap_base +
+ PCI_EXP_LNKCAP);
+ val &= ~PCI_EXP_LNKCAP_SLS;
+ val |= pcie->max_speed;
+ dw_pcie_writel_dbi(pci, pcie->pcie_cap_base + PCI_EXP_LNKCAP,
+ val);
+ }
+
+ clk_set_rate(pcie->core_clk, GEN4_CORE_CLK_FREQ);
+
+ val = (ep->msi_mem_phys & MSIX_ADDR_MATCH_LOW_OFF_MASK);
+ val |= MSIX_ADDR_MATCH_LOW_OFF_EN;
+ dw_pcie_writel_dbi(pci, MSIX_ADDR_MATCH_LOW_OFF, val);
+ val = (lower_32_bits(ep->msi_mem_phys) & MSIX_ADDR_MATCH_HIGH_OFF_MASK);
+ dw_pcie_writel_dbi(pci, MSIX_ADDR_MATCH_HIGH_OFF, val);
+
+ ret = dw_pcie_ep_init_complete(ep);
+ if (ret) {
+ dev_err(dev, "Failed to complete initialization: %d\n", ret);
+ goto fail_init_complete;
+ }
+
+ dw_pcie_ep_init_notify(ep);
+
+ /* Enable LTSSM */
+ val = appl_readl(pcie, APPL_CTRL);
+ val |= APPL_CTRL_LTSSM_EN;
+ appl_writel(pcie, val, APPL_CTRL);
+
+ pcie->ep_state = EP_STATE_ENABLED;
+ dev_dbg(dev, "Initialization of endpoint is completed\n");
+
+ return;
+
+fail_init_complete:
+ reset_control_assert(pcie->core_rst);
+ tegra_pcie_disable_phy(pcie);
+fail_phy:
+ reset_control_assert(pcie->core_apb_rst);
+fail_core_apb_rst:
+ clk_disable_unprepare(pcie->core_clk);
+fail_core_clk_enable:
+ tegra_pcie_bpmp_set_pll_state(pcie, false);
+fail_pll_init:
+ pm_runtime_put_sync(dev);
+}
+
+static void pex_ep_event_hot_rst_done(struct tegra_pcie_dw *pcie)
+{
+ u32 val;
+
+ appl_writel(pcie, 0xFFFFFFFF, APPL_INTR_STATUS_L0);
+ appl_writel(pcie, 0xFFFFFFFF, APPL_INTR_STATUS_L1_0_0);
+ appl_writel(pcie, 0xFFFFFFFF, APPL_INTR_STATUS_L1_1);
+ appl_writel(pcie, 0xFFFFFFFF, APPL_INTR_STATUS_L1_2);
+ appl_writel(pcie, 0xFFFFFFFF, APPL_INTR_STATUS_L1_3);
+ appl_writel(pcie, 0xFFFFFFFF, APPL_INTR_STATUS_L1_6);
+ appl_writel(pcie, 0xFFFFFFFF, APPL_INTR_STATUS_L1_7);
+ appl_writel(pcie, 0xFFFFFFFF, APPL_INTR_STATUS_L1_8_0);
+ appl_writel(pcie, 0xFFFFFFFF, APPL_INTR_STATUS_L1_9);
+ appl_writel(pcie, 0xFFFFFFFF, APPL_INTR_STATUS_L1_10);
+ appl_writel(pcie, 0xFFFFFFFF, APPL_INTR_STATUS_L1_11);
+ appl_writel(pcie, 0xFFFFFFFF, APPL_INTR_STATUS_L1_13);
+ appl_writel(pcie, 0xFFFFFFFF, APPL_INTR_STATUS_L1_14);
+ appl_writel(pcie, 0xFFFFFFFF, APPL_INTR_STATUS_L1_15);
+ appl_writel(pcie, 0xFFFFFFFF, APPL_INTR_STATUS_L1_17);
+ appl_writel(pcie, 0xFFFFFFFF, APPL_MSI_CTRL_2);
+
+ val = appl_readl(pcie, APPL_CTRL);
+ val |= APPL_CTRL_LTSSM_EN;
+ appl_writel(pcie, val, APPL_CTRL);
+}
+
+static void pex_ep_event_bme_change(struct tegra_pcie_dw *pcie)
+{
+ struct dw_pcie *pci = &pcie->pci;
+ u32 val, speed;
+
+ /* If EP doesn't advertise L1SS, just return */
+ val = dw_pcie_readl_dbi(pci, pcie->cfg_link_cap_l1sub);
+ if (!(val & (PCI_L1SS_CAP_ASPM_L1_1 | PCI_L1SS_CAP_ASPM_L1_2)))
+ return;
+
+ /* Check if BME is set to '1' */
+ val = dw_pcie_readl_dbi(pci, PCI_COMMAND);
+ if (val & PCI_COMMAND_MASTER) {
+ ktime_t timeout;
+
+ /* 110us for both snoop and no-snoop */
+ val = 110 | (2 << PCI_LTR_SCALE_SHIFT) | LTR_MSG_REQ;
+ val |= (val << LTR_MST_NO_SNOOP_SHIFT);
+ appl_writel(pcie, val, APPL_LTR_MSG_1);
+
+ /* Send LTR upstream */
+ val = appl_readl(pcie, APPL_LTR_MSG_2);
+ val |= APPL_LTR_MSG_2_LTR_MSG_REQ_STATE;
+ appl_writel(pcie, val, APPL_LTR_MSG_2);
+
+ timeout = ktime_add_us(ktime_get(), LTR_MSG_TIMEOUT);
+ for (;;) {
+ val = appl_readl(pcie, APPL_LTR_MSG_2);
+ if (!(val & APPL_LTR_MSG_2_LTR_MSG_REQ_STATE))
+ break;
+ if (ktime_after(ktime_get(), timeout))
+ break;
+ usleep_range(1000, 1100);
+ }
+ if (val & APPL_LTR_MSG_2_LTR_MSG_REQ_STATE)
+ dev_err(pcie->dev, "Failed to send LTR message\n");
+ }
+
+ speed = dw_pcie_readw_dbi(pci, pcie->pcie_cap_base + PCI_EXP_LNKSTA) &
+ PCI_EXP_LNKSTA_CLS;
+ clk_set_rate(pcie->core_clk, pcie_gen_freq[speed - 1]);
+}
+
+static int tegra_pcie_ep_work_thread(void *p)
+{
+ struct tegra_pcie_dw *pcie = (struct tegra_pcie_dw *)p;
+ u32 event;
+
+ while (true) {
+ wait_event_interruptible(pcie->wq,
+ !kfifo_is_empty(&pcie->event_fifo));
+
+ if (kthread_should_stop())
+ break;
+
+ if (!kfifo_get(&pcie->event_fifo, &event)) {
+ dev_warn(pcie->dev, "EVENT FIFO is empty\n");
+ continue;
+ }
+
+ switch (event) {
+ case EP_PEX_RST_DEASSERT:
+ dev_info(pcie->dev, "EVENT: EP_PEX_RST_DEASSERT\n");
+ pex_ep_event_pex_rst_deassert(pcie);
+ break;
+
+ case EP_PEX_RST_ASSERT:
+ dev_info(pcie->dev, "EVENT: EP_PEX_RST_ASSERT\n");
+ pex_ep_event_pex_rst_assert(pcie);
+ break;
+
+ case EP_HOT_RST_DONE:
+ dev_info(pcie->dev, "EVENT: EP_HOT_RST_DONE\n");
+ pex_ep_event_hot_rst_done(pcie);
+ break;
+
+ case EP_BME_CHANGE:
+ dev_info(pcie->dev, "EVENT: EP_BME_CHANGE\n");
+ pex_ep_event_bme_change(pcie);
+ break;
+
+ case EP_EVENT_EXIT:
+ dev_info(pcie->dev, "EVENT: EP_EVENT_EXIT\n");
+ return 0;
+
+ default:
+ dev_warn(pcie->dev, "Invalid PCIe EP event: %u\n",
+ event);
+ break;
+ }
+ }
+
+ return 0;
+}
+
+static irqreturn_t tegra_pcie_ep_pex_rst_irq(int irq, void *arg)
+{
+ struct tegra_pcie_dw *pcie = arg;
+
+ if (gpiod_get_value(pcie->pex_rst_gpiod)) {
+ if (!kfifo_put(&pcie->event_fifo, EP_PEX_RST_ASSERT)) {
+ dev_err(pcie->dev, "EVENT FIFO is full\n");
+ return IRQ_HANDLED;
+ }
+ } else {
+ if (!kfifo_put(&pcie->event_fifo, EP_PEX_RST_DEASSERT)) {
+ dev_err(pcie->dev, "EVENT FIFO is full\n");
+ return IRQ_HANDLED;
+ }
+ }
+
+ wake_up(&pcie->wq);
+
+ return IRQ_HANDLED;
+}
+
+static int tegra_pcie_ep_raise_legacy_irq(struct tegra_pcie_dw *pcie, u16 irq)
+{
+ /* Tegra194 supports only INTA */
+ if (irq > 1)
+ return -EINVAL;
+
+ appl_writel(pcie, 1, APPL_LEGACY_INTX);
+ usleep_range(1000, 2000);
+ appl_writel(pcie, 0, APPL_LEGACY_INTX);
+ return 0;
+}
+
+static int tegra_pcie_ep_raise_msi_irq(struct tegra_pcie_dw *pcie, u16 irq)
+{
+ if (unlikely(irq > 31))
+ return -EINVAL;
+
+ appl_writel(pcie, (1 << irq), APPL_MSI_CTRL_1);
+
+ return 0;
+}
+
+static int tegra_pcie_ep_raise_msix_irq(struct tegra_pcie_dw *pcie, u16 irq)
+{
+ struct dw_pcie_ep *ep = &pcie->pci.ep;
+
+ writel(irq, ep->msi_mem);
+
+ return 0;
+}
+
+static int tegra_pcie_ep_raise_irq(struct dw_pcie_ep *ep, u8 func_no,
+ enum pci_epc_irq_type type,
+ u16 interrupt_num)
+{
+ struct dw_pcie *pci = to_dw_pcie_from_ep(ep);
+ struct tegra_pcie_dw *pcie = to_tegra_pcie(pci);
+
+ switch (type) {
+ case PCI_EPC_IRQ_LEGACY:
+ return tegra_pcie_ep_raise_legacy_irq(pcie, interrupt_num);
+
+ case PCI_EPC_IRQ_MSI:
+ return tegra_pcie_ep_raise_msi_irq(pcie, interrupt_num);
+
+ case PCI_EPC_IRQ_MSIX:
+ return tegra_pcie_ep_raise_msix_irq(pcie, interrupt_num);
+
+ default:
+ dev_err(pci->dev, "Unknown IRQ type\n");
+ return -EPERM;
+ }
+
+ return 0;
+}
+
+static const struct pci_epc_features tegra_pcie_epc_features = {
+ .linkup_notifier = true,
+ .core_init_notifier = true,
+ .msi_capable = false,
+ .msix_capable = false,
+ .reserved_bar = 1 << BAR_2 | 1 << BAR_3 | 1 << BAR_4 | 1 << BAR_5,
+ .bar_fixed_64bit = 1 << BAR_0,
+ .bar_fixed_size[0] = SZ_1M,
+};
+
+static const struct pci_epc_features*
+tegra_pcie_ep_get_features(struct dw_pcie_ep *ep)
+{
+ return &tegra_pcie_epc_features;
+}
+
+static struct dw_pcie_ep_ops pcie_ep_ops = {
+ .raise_irq = tegra_pcie_ep_raise_irq,
+ .get_features = tegra_pcie_ep_get_features,
+};
+
+static int tegra_pcie_config_ep(struct tegra_pcie_dw *pcie,
+ struct platform_device *pdev)
+{
+ struct dw_pcie *pci = &pcie->pci;
+ struct device *dev = pcie->dev;
+ struct dw_pcie_ep *ep;
+ struct resource *res;
+ char *name;
+ int ret;
+
+ ep = &pci->ep;
+ ep->ops = &pcie_ep_ops;
+
+ res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "addr_space");
+ if (!res)
+ return -EINVAL;
+
+ ep->phys_base = res->start;
+ ep->addr_size = resource_size(res);
+ ep->page_size = SZ_64K;
+
+ ret = gpiod_set_debounce(pcie->pex_rst_gpiod, PERST_DEBOUNCE_TIME);
+ if (ret < 0) {
+ dev_err(dev, "Failed to set PERST GPIO debounce time: %d\n",
+ ret);
+ return ret;
+ }
+
+ ret = gpiod_to_irq(pcie->pex_rst_gpiod);
+ if (ret < 0) {
+ dev_err(dev, "Failed to get IRQ for PERST GPIO: %d\n", ret);
+ return ret;
+ }
+ pcie->pex_rst_irq = (unsigned int)ret;
+
+ name = devm_kasprintf(dev, GFP_KERNEL, "tegra_pcie_%u_pex_rst_irq",
+ pcie->cid);
+ if (!name) {
+ dev_err(dev, "Failed to create PERST IRQ string\n");
+ return -ENOMEM;
+ }
+
+ irq_set_status_flags(pcie->pex_rst_irq, IRQ_NOAUTOEN);
+
+ ret = devm_request_irq(dev, pcie->pex_rst_irq,
+ tegra_pcie_ep_pex_rst_irq,
+ IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING,
+ name, (void *)pcie);
+ if (ret < 0) {
+ dev_err(dev, "Failed to request IRQ for PERST: %d\n", ret);
+ return ret;
+ }
+
+ pcie->ep_state = EP_STATE_DISABLED;
+
+ INIT_KFIFO(pcie->event_fifo);
+
+ init_waitqueue_head(&pcie->wq);
+
+ name = devm_kasprintf(dev, GFP_KERNEL, "tegra_pcie_%u_ep_work",
+ pcie->cid);
+ if (!name) {
+ dev_err(dev, "Failed to create PCIe EP work thread string\n");
+ return -ENOMEM;
+ }
+ pcie->pcie_ep_task = kthread_run(tegra_pcie_ep_work_thread,
+ (void *)pcie, name);
+ if (IS_ERR(pcie->pcie_ep_task)) {
+ dev_err(dev, "Failed to create PCIe EP work thread: %d\n",
+ PTR_ERR_OR_ZERO(pcie->pcie_ep_task));
+ return PTR_ERR_OR_ZERO(pcie->pcie_ep_task);
+ }
+
+ pm_runtime_enable(dev);
+
+ ret = dw_pcie_ep_init(ep);
+ if (ret) {
+ dev_err(dev, "Failed to initialize DWC Endpoint subsystem: %d\n",
+ ret);
+ return ret;
+ }
+
+ return 0;
+}
+
static int tegra_pcie_dw_probe(struct platform_device *pdev)
{
+ const struct tegra_pcie_dw_of_data *data;
struct device *dev = &pdev->dev;
struct resource *atu_dma_res;
struct tegra_pcie_dw *pcie;
@@ -1440,6 +2137,8 @@ static int tegra_pcie_dw_probe(struct platform_device *pdev)
int ret;
u32 i;

+ data = of_device_get_match_data(dev);
+
pcie = devm_kzalloc(dev, sizeof(*pcie), GFP_KERNEL);
if (!pcie)
return -ENOMEM;
@@ -1449,6 +2148,7 @@ static int tegra_pcie_dw_probe(struct platform_device *pdev)
pci->ops = &tegra_dw_pcie_ops;
pp = &pci->pp;
pcie->dev = &pdev->dev;
+ pcie->mode = (enum dw_pcie_device_mode)data->mode;

ret = tegra_pcie_dw_parse_dt(pcie);
if (ret < 0) {
@@ -1462,6 +2162,9 @@ static int tegra_pcie_dw_probe(struct platform_device *pdev)
return ret;
}

+ if (pcie->pex_refclk_sel_gpiod)
+ gpiod_set_value(pcie->pex_refclk_sel_gpiod, 1);
+
pcie->pex_ctl_supply = devm_regulator_get(dev, "vddio-pex-ctl");
if (IS_ERR(pcie->pex_ctl_supply)) {
ret = PTR_ERR(pcie->pex_ctl_supply);
@@ -1557,24 +2260,46 @@ static int tegra_pcie_dw_probe(struct platform_device *pdev)
return -ENODEV;
}

- ret = devm_request_irq(dev, pp->irq, tegra_pcie_irq_handler,
- IRQF_SHARED, "tegra-pcie-intr", pcie);
- if (ret) {
- dev_err(dev, "Failed to request IRQ %d: %d\n", pp->irq, ret);
- return ret;
- }
-
pcie->bpmp = tegra_bpmp_get(dev);
if (IS_ERR(pcie->bpmp))
return PTR_ERR(pcie->bpmp);

platform_set_drvdata(pdev, pcie);

- ret = tegra_pcie_config_rp(pcie);
- if (ret && ret != -ENOMEDIUM)
- goto fail;
- else
- return 0;
+ switch (pcie->mode) {
+ case DW_PCIE_RC_TYPE:
+ ret = devm_request_irq(dev, pp->irq, tegra_pcie_rp_irq_handler,
+ IRQF_SHARED, "tegra-pcie-intr", pcie);
+ if (ret) {
+ dev_err(dev, "Failed to request IRQ %d: %d\n", pp->irq,
+ ret);
+ goto fail;
+ }
+
+ ret = tegra_pcie_config_rp(pcie);
+ if (ret && ret != -ENOMEDIUM)
+ goto fail;
+ else
+ return 0;
+ break;
+
+ case DW_PCIE_EP_TYPE:
+ ret = devm_request_irq(dev, pp->irq, tegra_pcie_ep_irq_handler,
+ IRQF_SHARED, "tegra-pcie-ep-intr", pcie);
+ if (ret) {
+ dev_err(dev, "Failed to request IRQ %d: %d\n", pp->irq,
+ ret);
+ goto fail;
+ }
+
+ ret = tegra_pcie_config_ep(pcie, pdev);
+ if (ret < 0)
+ goto fail;
+ break;
+
+ default:
+ dev_err(dev, "Invalid PCIe device type %d\n", pcie->mode);
+ }

fail:
tegra_bpmp_put(pcie->bpmp);
@@ -1593,6 +2318,8 @@ static int tegra_pcie_dw_remove(struct platform_device *pdev)
pm_runtime_put_sync(pcie->dev);
pm_runtime_disable(pcie->dev);
tegra_bpmp_put(pcie->bpmp);
+ if (pcie->pex_refclk_sel_gpiod)
+ gpiod_set_value(pcie->pex_refclk_sel_gpiod, 0);

return 0;
}
@@ -1697,9 +2424,22 @@ static void tegra_pcie_dw_shutdown(struct platform_device *pdev)
__deinit_controller(pcie);
}

+static const struct tegra_pcie_dw_of_data tegra_pcie_dw_rc_of_data = {
+ .mode = DW_PCIE_RC_TYPE,
+};
+
+static const struct tegra_pcie_dw_of_data tegra_pcie_dw_ep_of_data = {
+ .mode = DW_PCIE_EP_TYPE,
+};
+
static const struct of_device_id tegra_pcie_dw_of_match[] = {
{
.compatible = "nvidia,tegra194-pcie",
+ .data = &tegra_pcie_dw_rc_of_data,
+ },
+ {
+ .compatible = "nvidia,tegra194-pcie-ep",
+ .data = &tegra_pcie_dw_ep_of_data,
},
{},
};
--
2.17.1